INFORMATION TECHNOLOGY IS CONSIDERED A MAJOR THREAT TO privacy because it enables pervasive surveillance, massive databases, and lightning- speed distribution of information across the globe. In fact, privacy has been one of the most enduring social issues associated with digital electronic information technologies. A fi xture in public discourse at least since the 1960s, when the dominant concern was massive databases of government and other large institutions housed in large stand- alone computers, concerns have multiplied in type and extent as radical transformations of the technology have yielded the remarkable range of present- day systems, including distributed networking; the World Wide Web; mobile devices; video, audio, and biometric surveillance; global positioning; ubiquitous computing; social networks; sensor networks; databases of compiled information; data mining; and more. Associated with each of these developments is a set of worries about privacy.